To expand a bit on the last thought in my quasi-philosophical post of Friday:
The only people in the park for whom the correct call is the priority are the umpires. The players, managers, coaches, even the fans — what they want is the call that helps their team.
I'm bound to complain about whatever form of replay eventually infects major league baseball. No matter the format, it will be an imperfect pursuit of perfection.
But I will complain most bitterly if the format relies (as does the NFL's) on a challenge system. Baseball would do better to squeeze more of the dead time out of the game, not add to it. There are certain managers — Joe Torre, Tony La Russa, Joe Girardi, Terry Francona — who have made stalling the game an art form. Giving them another tool to do that is a really bad idea.
Install an NFL-type system, and I guarantee you that on some 35-degree World Series night some manager will use a challenge to make the opposing pitcher freeze in his own sweat while an umpire goes into the peep-show booth.
Keep the managers out of the system. Their interests are not baseball's interests.